[968] | 1 | // |
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| 2 | // ******************************************************************** |
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| 3 | // * License and Disclaimer * |
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| 4 | // * * |
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| 5 | // * The Geant4 software is copyright of the Copyright Holders of * |
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| 6 | // * the Geant4 Collaboration. It is provided under the terms and * |
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| 7 | // * conditions of the Geant4 Software License, included in the file * |
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| 8 | // * LICENSE and available at http://cern.ch/geant4/license . These * |
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| 9 | // * include a list of copyright holders. * |
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| 10 | // * * |
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| 11 | // * Neither the authors of this software system, nor their employing * |
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| 12 | // * institutes,nor the agencies providing financial support for this * |
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| 13 | // * work make any representation or warranty, express or implied, * |
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| 14 | // * regarding this software system or assume any liability for its * |
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| 15 | // * use. Please see the license in the file LICENSE and URL above * |
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| 16 | // * for the full disclaimer and the limitation of liability. * |
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| 17 | // * * |
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| 18 | // * This code implementation is the result of the scientific and * |
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| 19 | // * technical work of the GEANT4 collaboration. * |
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| 20 | // * By using, copying, modifying or distributing the software (or * |
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| 21 | // * any work based on the software) you agree to acknowledge its * |
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| 22 | // * use in resulting scientific publications, and indicate your * |
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| 23 | // * acceptance of all terms of the Geant4 Software license. * |
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| 24 | // ******************************************************************** |
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| 25 | // |
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[1347] | 26 | // $Id: G4PenelopePhotoElectricModel.cc,v 1.13 2010/11/26 11:51:11 pandola Exp $ |
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| 27 | // GEANT4 tag $Name: geant4-09-04-ref-00 $ |
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[968] | 28 | // |
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| 29 | // Author: Luciano Pandola |
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| 30 | // |
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| 31 | // History: |
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| 32 | // -------- |
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[1055] | 33 | // 08 Oct 2008 L Pandola Migration from process to model |
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| 34 | // 08 Jan 2009 L Pandola Check shell index to avoid mismatch between |
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| 35 | // the Penelope cross section database and the |
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| 36 | // G4AtomicTransitionManager database. It suppresses |
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| 37 | // a warning from G4AtomicTransitionManager only. |
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| 38 | // Results are unchanged. |
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| 39 | // 25 Mar 2009 L Pandola Small fix to avoid wrong energy-violation warnings |
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| 40 | // 17 Apr 2009 V Ivanchenko Cleanup initialisation and generation of secondaries: |
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| 41 | // - apply internal high-energy limit only in constructor |
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| 42 | // - do not apply low-energy limit (default is 0) |
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| 43 | // - do not apply production threshold on secondaries |
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| 44 | // 19 May 2009 L Pandola Explicitely set to zero pointers deleted in |
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| 45 | // Initialise(), since they might be checked later on |
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[1192] | 46 | // 21 Oct 2009 L Pandola Remove un-necessary fUseAtomicDeexcitation flag - now managed by |
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| 47 | // G4VEmModel::DeexcitationFlag() |
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[1315] | 48 | // 15 Mar 2010 L Pandola Explicitely initialize Auger to false |
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[968] | 49 | // |
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| 50 | |
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| 51 | #include "G4PenelopePhotoElectricModel.hh" |
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| 52 | #include "G4ParticleDefinition.hh" |
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| 53 | #include "G4MaterialCutsCouple.hh" |
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| 54 | #include "G4ProductionCutsTable.hh" |
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| 55 | #include "G4DynamicParticle.hh" |
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| 56 | #include "G4PhysicsTable.hh" |
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| 57 | #include "G4ElementTable.hh" |
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| 58 | #include "G4Element.hh" |
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| 59 | #include "G4CrossSectionHandler.hh" |
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| 60 | #include "G4AtomicTransitionManager.hh" |
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| 61 | #include "G4AtomicShell.hh" |
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| 62 | #include "G4Gamma.hh" |
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| 63 | #include "G4Electron.hh" |
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[1347] | 64 | #include "G4VEMDataSet.hh" |
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[968] | 65 | |
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| 66 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 67 | |
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| 68 | |
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| 69 | G4PenelopePhotoElectricModel::G4PenelopePhotoElectricModel(const G4ParticleDefinition*, |
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| 70 | const G4String& nam) |
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| 71 | :G4VEmModel(nam),isInitialised(false),crossSectionHandler(0), |
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| 72 | shellCrossSectionHandler(0) |
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| 73 | { |
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| 74 | fIntrinsicLowEnergyLimit = 100.0*eV; |
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| 75 | fIntrinsicHighEnergyLimit = 100.0*GeV; |
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[1055] | 76 | // SetLowEnergyLimit(fIntrinsicLowEnergyLimit); |
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[968] | 77 | SetHighEnergyLimit(fIntrinsicHighEnergyLimit); |
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| 78 | // |
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| 79 | verboseLevel= 0; |
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| 80 | // Verbosity scale: |
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| 81 | // 0 = nothing |
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| 82 | // 1 = warning for energy non-conservation |
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| 83 | // 2 = details of energy budget |
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| 84 | // 3 = calculation of cross sections, file openings, sampling of atoms |
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| 85 | // 4 = entering in methods |
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[1315] | 86 | |
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| 87 | //by default the model will inkove the atomic deexcitation |
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| 88 | SetDeexcitationFlag(true); |
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| 89 | ActivateAuger(false); |
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[968] | 90 | } |
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| 91 | |
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| 92 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 93 | |
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| 94 | G4PenelopePhotoElectricModel::~G4PenelopePhotoElectricModel() |
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| 95 | { |
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| 96 | if (crossSectionHandler) delete crossSectionHandler; |
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| 97 | if (shellCrossSectionHandler) delete shellCrossSectionHandler; |
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| 98 | } |
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| 99 | |
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| 100 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 101 | |
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| 102 | void G4PenelopePhotoElectricModel::Initialise(const G4ParticleDefinition*, |
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| 103 | const G4DataVector& ) |
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| 104 | { |
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| 105 | if (verboseLevel > 3) |
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| 106 | G4cout << "Calling G4PenelopePhotoElectricModel::Initialise()" << G4endl; |
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| 107 | if (crossSectionHandler) |
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| 108 | { |
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| 109 | crossSectionHandler->Clear(); |
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| 110 | delete crossSectionHandler; |
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[1055] | 111 | crossSectionHandler = 0; |
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[968] | 112 | } |
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| 113 | if (shellCrossSectionHandler) |
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| 114 | { |
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| 115 | shellCrossSectionHandler->Clear(); |
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| 116 | delete shellCrossSectionHandler; |
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[1055] | 117 | shellCrossSectionHandler =0; |
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[968] | 118 | } |
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| 119 | |
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| 120 | //Re-initialize cross section handlers |
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| 121 | crossSectionHandler = new G4CrossSectionHandler(); |
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| 122 | crossSectionHandler->Clear(); |
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| 123 | G4String crossSectionFile = "penelope/ph-cs-pen-"; |
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| 124 | crossSectionHandler->LoadData(crossSectionFile); |
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| 125 | shellCrossSectionHandler = new G4CrossSectionHandler(); |
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| 126 | shellCrossSectionHandler->Clear(); |
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| 127 | crossSectionFile = "penelope/ph-ss-cs-pen-"; |
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| 128 | shellCrossSectionHandler->LoadShellData(crossSectionFile); |
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| 129 | //This is used to retrieve cross section values later on |
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[1347] | 130 | G4VEMDataSet* emdata = |
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| 131 | crossSectionHandler->BuildMeanFreePathForMaterials(); |
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| 132 | //The method BuildMeanFreePathForMaterials() is required here only to force |
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| 133 | //the building of an internal table: the output pointer can be deleted |
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| 134 | delete emdata; |
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[968] | 135 | |
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| 136 | if (verboseLevel > 2) |
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| 137 | G4cout << "Loaded cross section files for PenelopePhotoElectric" << G4endl; |
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| 138 | |
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[1055] | 139 | if (verboseLevel > 0) { |
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| 140 | G4cout << "Penelope Photo-Electric model is initialized " << G4endl |
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| 141 | << "Energy range: " |
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| 142 | << LowEnergyLimit() / MeV << " MeV - " |
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| 143 | << HighEnergyLimit() / GeV << " GeV" |
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| 144 | << G4endl; |
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| 145 | } |
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[968] | 146 | |
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| 147 | if(isInitialised) return; |
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[1055] | 148 | fParticleChange = GetParticleChangeForGamma(); |
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[968] | 149 | isInitialised = true; |
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| 150 | } |
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| 151 | |
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| 152 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 153 | |
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| 154 | G4double G4PenelopePhotoElectricModel::ComputeCrossSectionPerAtom( |
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| 155 | const G4ParticleDefinition*, |
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| 156 | G4double energy, |
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| 157 | G4double Z, G4double, |
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| 158 | G4double, G4double) |
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| 159 | { |
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| 160 | // |
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| 161 | // Penelope model. Use data-driven approach for cross section estimate (and |
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| 162 | // also shell sampling from a given atom). Data are from the Livermore database |
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| 163 | // D.E. Cullen et al., Report UCRL-50400 (1989) |
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| 164 | // |
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| 165 | |
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| 166 | if (verboseLevel > 3) |
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| 167 | G4cout << "Calling ComputeCrossSectionPerAtom() of G4PenelopePhotoElectricModel" << G4endl; |
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| 168 | |
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| 169 | G4int iZ = (G4int) Z; |
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[1055] | 170 | // if (!crossSectionHandler) // VI: should not be |
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| 171 | // { |
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| 172 | // G4cout << "G4PenelopePhotoElectricModel::ComputeCrossSectionPerAtom" << G4endl; |
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| 173 | // G4cout << "The cross section handler is not correctly initialized" << G4endl; |
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| 174 | // G4Exception(); |
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| 175 | // } |
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[968] | 176 | G4double cs = crossSectionHandler->FindValue(iZ,energy); |
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| 177 | |
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| 178 | if (verboseLevel > 2) |
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| 179 | G4cout << "Photoelectric cross section at " << energy/MeV << " MeV for Z=" << Z << |
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| 180 | " = " << cs/barn << " barn" << G4endl; |
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| 181 | return cs; |
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| 182 | } |
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| 183 | |
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| 184 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 185 | |
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| 186 | void G4PenelopePhotoElectricModel::SampleSecondaries(std::vector<G4DynamicParticle*>* fvect, |
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| 187 | const G4MaterialCutsCouple* couple, |
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| 188 | const G4DynamicParticle* aDynamicGamma, |
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| 189 | G4double, |
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| 190 | G4double) |
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| 191 | { |
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| 192 | // |
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| 193 | // Photoelectric effect, Penelope model |
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| 194 | // |
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| 195 | // The target atom and the target shell are sampled according to the Livermore |
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| 196 | // database |
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| 197 | // D.E. Cullen et al., Report UCRL-50400 (1989) |
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| 198 | // The angular distribution of the electron in the final state is sampled |
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| 199 | // according to the Sauter distribution from |
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| 200 | // F. Sauter, Ann. Phys. 11 (1931) 454 |
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| 201 | // The energy of the final electron is given by the initial photon energy minus |
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| 202 | // the binding energy. Fluorescence de-excitation is subsequently produced |
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| 203 | // (to fill the vacancy) according to the general Geant4 G4DeexcitationManager: |
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| 204 | // J. Stepanek, Comp. Phys. Comm. 1206 pp 1-1-9 (1997) |
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| 205 | |
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| 206 | if (verboseLevel > 3) |
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| 207 | G4cout << "Calling SamplingSecondaries() of G4PenelopePhotoElectricModel" << G4endl; |
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| 208 | |
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| 209 | G4double photonEnergy = aDynamicGamma->GetKineticEnergy(); |
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| 210 | |
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[1055] | 211 | // always kill primary |
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| 212 | fParticleChange->ProposeTrackStatus(fStopAndKill); |
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| 213 | fParticleChange->SetProposedKineticEnergy(0.); |
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| 214 | |
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| 215 | if (photonEnergy <= fIntrinsicLowEnergyLimit) |
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| 216 | { |
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[968] | 217 | fParticleChange->ProposeLocalEnergyDeposit(photonEnergy); |
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| 218 | return ; |
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[1055] | 219 | } |
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[968] | 220 | |
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| 221 | G4ParticleMomentum photonDirection = aDynamicGamma->GetMomentumDirection(); |
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| 222 | |
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| 223 | // Select randomly one element in the current material |
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| 224 | if (verboseLevel > 2) |
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| 225 | G4cout << "Going to select element in " << couple->GetMaterial()->GetName() << G4endl; |
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| 226 | //use crossSectionHandler instead of G4EmElementSelector because in this case |
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[1055] | 227 | //the dimension of the table is equal to the dimension of the database |
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| 228 | //(less interpolation errors) |
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[968] | 229 | G4int Z = crossSectionHandler->SelectRandomAtom(couple,photonEnergy); |
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| 230 | if (verboseLevel > 2) |
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| 231 | G4cout << "Selected Z = " << Z << G4endl; |
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| 232 | |
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| 233 | // Select the ionised shell in the current atom according to shell cross sections |
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| 234 | size_t shellIndex = shellCrossSectionHandler->SelectRandomShell(Z,photonEnergy); |
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| 235 | |
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| 236 | // Retrieve the corresponding identifier and binding energy of the selected shell |
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| 237 | const G4AtomicTransitionManager* transitionManager = G4AtomicTransitionManager::Instance(); |
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[1055] | 238 | |
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| 239 | //The number of shell cross section possibly reported in the Penelope database |
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| 240 | //might be different from the number of shells in the G4AtomicTransitionManager |
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| 241 | //(namely, Penelope may contain more shell, especially for very light elements). |
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| 242 | //In order to avoid a warning message from the G4AtomicTransitionManager, I |
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| 243 | //add this protection. Results are anyway changed, because when G4AtomicTransitionManager |
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| 244 | //has a shellID>maxID, it sets the shellID to the last valid shell. |
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| 245 | size_t numberOfShells = (size_t) transitionManager->NumberOfShells(Z); |
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| 246 | if (shellIndex >= numberOfShells) |
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| 247 | shellIndex = numberOfShells-1; |
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| 248 | |
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[968] | 249 | const G4AtomicShell* shell = transitionManager->Shell(Z,shellIndex); |
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| 250 | G4double bindingEnergy = shell->BindingEnergy(); |
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| 251 | G4int shellId = shell->ShellId(); |
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| 252 | |
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| 253 | G4double localEnergyDeposit = 0.0; |
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| 254 | |
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| 255 | // Primary outcoming electron |
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| 256 | G4double eKineticEnergy = photonEnergy - bindingEnergy; |
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| 257 | |
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| 258 | // There may be cases where the binding energy of the selected shell is > photon energy |
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| 259 | // In such cases do not generate secondaries |
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| 260 | if (eKineticEnergy > 0.) |
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[1315] | 261 | { |
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[1055] | 262 | // The electron is created |
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| 263 | // Direction sampled from the Sauter distribution |
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| 264 | G4double cosTheta = SampleElectronDirection(eKineticEnergy); |
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| 265 | G4double sinTheta = std::sqrt(1-cosTheta*cosTheta); |
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| 266 | G4double phi = twopi * G4UniformRand() ; |
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| 267 | G4double dirx = sinTheta * std::cos(phi); |
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| 268 | G4double diry = sinTheta * std::sin(phi); |
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| 269 | G4double dirz = cosTheta ; |
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| 270 | G4ThreeVector electronDirection(dirx,diry,dirz); //electron direction |
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| 271 | electronDirection.rotateUz(photonDirection); |
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| 272 | G4DynamicParticle* electron = new G4DynamicParticle (G4Electron::Electron(), |
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| 273 | electronDirection, |
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| 274 | eKineticEnergy); |
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| 275 | fvect->push_back(electron); |
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| 276 | } |
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[968] | 277 | else |
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[1055] | 278 | { |
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[968] | 279 | bindingEnergy = photonEnergy; |
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[1055] | 280 | } |
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[968] | 281 | G4double energyInFluorescence = 0; //testing purposes |
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| 282 | |
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| 283 | //Now, take care of fluorescence, if required |
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[1055] | 284 | if(DeexcitationFlag() && Z > 5) |
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[968] | 285 | { |
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[1055] | 286 | const G4ProductionCutsTable* theCoupleTable= |
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| 287 | G4ProductionCutsTable::GetProductionCutsTable(); |
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| 288 | size_t indx = couple->GetIndex(); |
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[968] | 289 | G4double cutG = (*(theCoupleTable->GetEnergyCutsVector(0)))[indx]; |
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[1055] | 290 | G4double cutE = (*(theCoupleTable->GetEnergyCutsVector(1)))[indx]; |
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[968] | 291 | |
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| 292 | // Protection to avoid generating photons in the unphysical case of |
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| 293 | // shell binding energy > photon energy |
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[1055] | 294 | if (bindingEnergy > cutG || bindingEnergy > cutE) |
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[968] | 295 | { |
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[1055] | 296 | deexcitationManager.SetCutForSecondaryPhotons(cutG); |
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| 297 | deexcitationManager.SetCutForAugerElectrons(cutE); |
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| 298 | std::vector<G4DynamicParticle*>* photonVector = |
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| 299 | deexcitationManager.GenerateParticles(Z,shellId); |
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| 300 | //Check for secondaries |
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| 301 | if(photonVector) |
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[968] | 302 | { |
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[1055] | 303 | for (size_t k=0; k< photonVector->size(); k++) |
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[968] | 304 | { |
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[1055] | 305 | G4DynamicParticle* aPhoton = (*photonVector)[k]; |
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| 306 | if (aPhoton) |
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[968] | 307 | { |
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[1055] | 308 | G4double itsEnergy = aPhoton->GetKineticEnergy(); |
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| 309 | if (itsEnergy <= bindingEnergy) |
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| 310 | { |
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| 311 | if(aPhoton->GetDefinition() == G4Gamma::Gamma()) |
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| 312 | energyInFluorescence += itsEnergy; |
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| 313 | bindingEnergy -= itsEnergy; |
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| 314 | fvect->push_back(aPhoton); |
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| 315 | } |
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| 316 | else |
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| 317 | { |
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| 318 | delete aPhoton; |
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| 319 | (*photonVector)[k] = 0; |
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| 320 | } |
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[968] | 321 | } |
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| 322 | } |
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[1055] | 323 | delete photonVector; |
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[968] | 324 | } |
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| 325 | } |
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| 326 | } |
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| 327 | //Residual energy is deposited locally |
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| 328 | localEnergyDeposit += bindingEnergy; |
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| 329 | |
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| 330 | if (localEnergyDeposit < 0) |
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| 331 | { |
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| 332 | G4cout << "WARNING - " |
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| 333 | << "G4PenelopePhotoElectric::PostStepDoIt - Negative energy deposit" |
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| 334 | << G4endl; |
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| 335 | localEnergyDeposit = 0; |
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| 336 | } |
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| 337 | |
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| 338 | fParticleChange->ProposeLocalEnergyDeposit(localEnergyDeposit); |
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| 339 | |
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| 340 | if (verboseLevel > 1) |
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| 341 | { |
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| 342 | G4cout << "-----------------------------------------------------------" << G4endl; |
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| 343 | G4cout << "Energy balance from G4PenelopePhotoElectric" << G4endl; |
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| 344 | G4cout << "Incoming photon energy: " << photonEnergy/keV << " keV" << G4endl; |
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| 345 | G4cout << "-----------------------------------------------------------" << G4endl; |
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| 346 | if (eKineticEnergy) |
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| 347 | G4cout << "Outgoing electron " << eKineticEnergy/keV << " keV" << G4endl; |
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| 348 | G4cout << "Fluorescence: " << energyInFluorescence/keV << " keV" << G4endl; |
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| 349 | G4cout << "Local energy deposit " << localEnergyDeposit/keV << " keV" << G4endl; |
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| 350 | G4cout << "Total final state: " << (eKineticEnergy+energyInFluorescence+localEnergyDeposit)/keV << |
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| 351 | " keV" << G4endl; |
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| 352 | G4cout << "-----------------------------------------------------------" << G4endl; |
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| 353 | } |
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| 354 | if (verboseLevel > 0) |
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| 355 | { |
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[1055] | 356 | G4double energyDiff = |
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| 357 | std::fabs(eKineticEnergy+energyInFluorescence+localEnergyDeposit-photonEnergy); |
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[968] | 358 | if (energyDiff > 0.05*keV) |
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| 359 | G4cout << "Warning from G4PenelopePhotoElectric: problem with energy conservation: " << |
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[1055] | 360 | (eKineticEnergy+energyInFluorescence+localEnergyDeposit)/keV |
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| 361 | << " keV (final) vs. " << |
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[968] | 362 | photonEnergy/keV << " keV (initial)" << G4endl; |
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| 363 | } |
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| 364 | } |
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| 365 | |
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| 366 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 367 | |
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| 368 | void G4PenelopePhotoElectricModel::ActivateAuger(G4bool augerbool) |
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| 369 | { |
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[1192] | 370 | if (!DeexcitationFlag() && augerbool) |
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[968] | 371 | { |
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| 372 | G4cout << "WARNING - G4PenelopePhotoElectricModel" << G4endl; |
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| 373 | G4cout << "The use of the Atomic Deexcitation Manager is set to false " << G4endl; |
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| 374 | G4cout << "Therefore, Auger electrons will be not generated anyway" << G4endl; |
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| 375 | } |
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| 376 | deexcitationManager.ActivateAugerElectronProduction(augerbool); |
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| 377 | if (verboseLevel > 1) |
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| 378 | G4cout << "Auger production set to " << augerbool << G4endl; |
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| 379 | } |
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| 380 | |
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| 381 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 382 | |
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| 383 | G4double G4PenelopePhotoElectricModel::SampleElectronDirection(G4double energy) |
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| 384 | { |
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| 385 | G4double costheta = 1.0; |
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| 386 | if (energy>1*GeV) return costheta; |
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| 387 | |
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| 388 | //1) initialize energy-dependent variables |
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| 389 | // Variable naming according to Eq. (2.24) of Penelope Manual |
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| 390 | // (pag. 44) |
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| 391 | G4double gamma = 1.0 + energy/electron_mass_c2; |
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| 392 | G4double gamma2 = gamma*gamma; |
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| 393 | G4double beta = std::sqrt((gamma2-1.0)/gamma2); |
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| 394 | |
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| 395 | // ac corresponds to "A" of Eq. (2.31) |
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| 396 | // |
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| 397 | G4double ac = (1.0/beta) - 1.0; |
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| 398 | G4double a1 = 0.5*beta*gamma*(gamma-1.0)*(gamma-2.0); |
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| 399 | G4double a2 = ac + 2.0; |
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| 400 | G4double gtmax = 2.0*(a1 + 1.0/ac); |
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| 401 | |
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| 402 | G4double tsam = 0; |
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| 403 | G4double gtr = 0; |
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| 404 | |
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| 405 | //2) sampling. Eq. (2.31) of Penelope Manual |
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| 406 | // tsam = 1-std::cos(theta) |
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| 407 | // gtr = rejection function according to Eq. (2.28) |
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| 408 | do{ |
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| 409 | G4double rand = G4UniformRand(); |
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| 410 | tsam = 2.0*ac * (2.0*rand + a2*std::sqrt(rand)) / (a2*a2 - 4.0*rand); |
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| 411 | gtr = (2.0 - tsam) * (a1 + 1.0/(ac+tsam)); |
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| 412 | }while(G4UniformRand()*gtmax > gtr); |
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| 413 | costheta = 1.0-tsam; |
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| 414 | return costheta; |
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| 415 | } |
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| 416 | |
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